Fuel tank gage



March 2, 1948. w.-MccAND| Ess FUEL TANK GAGE Filed May 5. 1945 Patented Mar. 2, v1948 UNITED. STATES PATENT OFFICE FUEL TANK GAGE William McCandless, Toledo, Ohio Application May 5, 1945, Serial No. 592,138

8 Claims. (Cl. i3-313) This invention relates to liquid level gages.

This invention has utility when incorporated in a liquid level gage-wherein the level indication is from a container in which the liquid is under a more or less turbulent condition such as the fuel in a tank carried on a vehicle. l

The invention is particularly advantageous in eliminating the` undesirable oscillations of the pointer Ion a gage, especially in a magnetic type electrical gage, which is caused by ripples on the surface of or by the surging of the fuel in the tank. This is effected by eliminating the rapid oscillations of the oat which controls the mechanism translating oscillations to the needle on an indicator.

An additional feature of the invention is to provide la relatively static portion or region within the body of liquid protectedl against the general surging of the liquid body as a whole, from which portion the oscillation dampening is controlled.

An additional advantage is to provide a differential between the float movement and the dampening means whereby a positive and nicety of control may be obtained.

Still another advantage is to provide a construction which may be readily inserted or withdrawn through a relatively small aperture of a closed vessel.

Other objects and advantages of this invention relating to the arrangement, operation and function of the related elements of the structure, to various details of construction, to co-mbinations of parts and to economies of manufacture, will be apparent to those skilled in the art upon consideration of the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification wherein like reference characters designate corresponding parts in the several views.

Referring to the drawings:

Fig. 1 is a side elevation lof the device mounted in operative position within a tank, parts being broken away and showing the indicator connections diagrammatically;

Fig. 2 is a View from the left of Fig. 1, parts being broken away; and v Fig. 3 is a side elevation of a modified control and tank construction.

A typical installation including the invention is herein shown as being mounted in a container l such as the Afuel tank of a motor Vehicle. This tank may have the usual ller opening (not shown) for introducing a quantity of liquid 2 fuel 2 thereinto. The level of the fuel is indicated by needle 3 moving across dial 4 of an indicator orgage 5, usually of the electromagnetic type and usually mounted on the dash of the tank-carrying vehicle.

The needle is controlled as follows. Float 6, buoyed on the surface of the fuel, i's embraced by the free end of arm l, the remote `end of such arm being attached toa gear segment 8 fixed on shaft 9 or otherwise mounted in relation to the shaft, causing the same to rotate as the iioat rises and falls in response to liquid uctuations. The shaft V.ll is carried by housing lil through a bearing sleeve 9a and extends thereinto to mount arm II movable in response to the shaft rotation to vary the resistance of a rheostatic device to be described hereinafter.

The housing I0 extends through aperture I2 through the tank I and is provided with'a lip I3. A cover I4 supports the lip I3 and provides a closure for the housing extending over and about the aperture rim to be mounted in place on gasket I5 by screws IB engaging threaded ring I6. Mounted on the cover plate I4, a conically- Vshaped resistance core I'I is provided, extending obliquely into said housing, carrying a coil of resistance wire I'Ia, along which the free end of arm II may wipe in its movement to change the energy fiow in circuit I8, thereby operating the indicator 5. The circuit I8 includes terminal I lb, which is mounted in insulated relation with cover I 4 and in circuit with resistance coil Ila. The circuit includes a source of energy I9 and a switch 20 which latter is usually opened and closed with the ignition switch of the motor vehicle. The arm II is grounded in the usual manner to complete the circuit.

The details of construction of the variable rheostatic device as applied to an electromagnetic telemetric device is disclosed and claimed in my co-pending application Serial No. 562,887 now Patent No. 2,423,603 issued July 8, 1947.

Without some dampening means cooperating with Lthe indicator operating mechanism each and Vevery ripple or wave on the liquid surface moves the float 6 and is instantly translated to the needle so that undesirable oscillations are usually present and are intensied by the roughness of the terrain, over which the vehicle may be passing. This undesirable condition is eliminated by the invention disclosed herein.

To this end, bracket 2l is mounted on the housing I0 to depend therefrom and provide bearings 22, 23 for vertical shaft 24extending downwardly into the liquid. This shaft earriespinion 25 in mesh with gear segment 8. Mounted on the shaft end remote from the pinion, and submerged in the liquid near the bottom of the tank, is a pair of paddles or vanes 25. The vanes may be made of relatively thin sheet metal having at least one edge 21 offset to supply rigidity thereto and are preferably pivotedly mounted on a stud 28, preferably fixed in an eye 2da on the lower end of the shaft 24 and provided with stops 29 to abut against the shaft in positioning such vanes in operative or approximately diametrically extending relationship. This construction permits the vanes to be folded along the shaft for ready insertion or withdrawal through the-aperture l2. The vanes may be easily passed through such aperture and be caused to unfold into operative position as shown in Fig. 1..

In some constructions it may be desirable to employ a single vane 3! and a suitable mountingV therefor is shown in Fig. 3 wherein the shaft 2li has offset 3| terminating in an eye embracing stud y32 through the vane Vand further held in position by clip 33 struckV out of the vane to engage the shaft. This single vane may lhave its wings 3K1 extend diametrically in opposite directions Yfrom the shaft and be reinforced by oifset 2i.

When the Afloat arm' tends to rise vor Vfall-with the ripples on the surface of the fuel, Ait must drive or-rotate the vanes in the liquid at a much `higher speed relative to its own movement due to the gear ratio between the gear sector 8 and the pinion 2,5. The resistance of the liquid against the paddles or wings retards to a point of elimination any short, quick movements of the float arm, thus damping out any undesirable oscillations and the subsequent jerking or quivering of the indicating needle 3. The normal, slow movement of the float arm, due to a change in thearnount of fuel in the tank, is not affected by the rotation of the paddles to any significant extent for, at very low rates of change, the liquidresisting factor is practically non-existent.

The operation of the device may be somewhat improved by surrounding the vfuel region, in which the blades rotate, by a baffle 34, which may be the rim of an auxiliary pan 35 on the bottom of the tank, as shown in Fig. l, or by having the blades or paddles located in a depression 35 in the bottom of the tank, as shown in Fig. 3. This eliminates any effect on the rotor by surging of the whole body of the liquid.

The paddles are placed as close to the bottom of the container as possible, so that they are immersed in the liquid at al1 times, except when the tank `is empty beyond the lower limit of the gage. The pan 35 or depression 35 also aids in this feature by retaining a sufficient quantity of liquid to act upon the .rotor to the point where the tank proper is empty.

It is vto be understood that .the above detailed description of the present invention is intended to disclose an embodiment thereof `to those skilled in the art, but that the invention is not to be construed as limited in its application tothe details of construction and arrangement of Vparts illustrated in the accompanying drawings, since the invention `is capable of being practiced and carried out in various ways without departing from the `spiritof the invention. The language used in the specification relating to the operation and function of the elements of the invention is employed for purposes of 4description and not of limitation.

What isclaimed and it is desired to secure by United `States Letters Patent:

1. In a gage for indicating a liquid level in a container, a float, mechanism for translating to an indicator the rise and fall of the float with the liquid, a member submerged in a segregated portion of the liquid and rotatable therein against the resistance of said liquid, and high ratio toothed gearing means interconnected with said member and mechanism, said gearing operable by movement of said float for rotating said member at a high rate of speed whereby resistance of the liquid to the rotation of the member is imparted to the float; providing a dampener connection against rapid oscillations of the float.

2. In a gage for indicating a liquid level in a container, a float, mechanism for translating to an indicator the rise and fall of the float with the liquid, a member submerged in the liquid and rotatable against the resistance thereof, and motion multiplying means interconnected with said member and mechanism for rotating the member by movement of saidiioat at high anguiar velocity, -whereby resistance Vof the liquid to the rotation'of the member is imparted to the float providing a Adampener Vconnection against rapid oscillations of thefloat.

3. Ina gagefor indicating a liquid level in a container, va float, means for translating to an indicator the rise and fall ofthe float, a rotatablemember submerged in the liquid, a shaft for support of the member, and gearing between-the shaft and said translating means providing a differential between the movements of the float and submerged member whereby resistance of the rotatable member against the liquid is imparted to the float, providing a dampener connection against rapid oscillations of said float.

4. The structure set forth in claim 3 wherein the submerged member includes at least one vane mounted on the shaft for rotary movement therewith against the resistance of the liquid when held in its normal position and having a pivotal connection with said shaft to permit movement with respect thereto and held in normal position by having means engaging the shaft.

5. In a liquid level gage of the class described, a float, a shaft from which the float is swingably mounted and which is rotated by the rise and fall of the float, an arm fixed upon said shaft, indicating mechanism operable by said arm, a gear xed upon the shaft, a pinion in mesh therewith, a shaft supporting said pinion and extending into the liquid and a submerged member fixed upon said latter shaft whereby the submerged member is oscillated by the rise and fall of said float.

6. The structure of claim 5 wherein the gear is of a substantially greater radius than the pinion.

'7. In a gage for indicating a liquid level in a container, a float, mechanism for translating to an indicator the rise and fall of the float with the liquid, a rotatable vane submerged in the liquid and adapted to be rotated against the resistance thereof, motion multiplying means interconnected between said vane and mechanism providing a dampener connection against oscillations of the float, and a bale about the vane between a portion of the liquid in which the vane rotates and the body of the liquid proper.

8. In a liquid gage of the class described, a float, a shaft from which the float is swingably mounted and which is rotated by the rise and fall of the float, an electric circuit including a resistance, an indicator and an arm fixed to said shaft and having its free end movable along the resistance, a gear xed upon said shaft, a pinion 5 6 in mesh therewith, a shaft carrying said pinion and extending into the liquid and a, vane in the UNITED STATES PATENTS liquid attached to said latter shaft for rotation Number Name Date by the gear through said pinion. 1,481,322 Kellum J an. 22, 1924 5 1,930,546 Bacon Oct. 17, 1933 WILLIAM MCCANDLESS. t FOREIGN PATENTS REFERENCES CITED Number Country Date The following references are of record in the 27,970 France June 24,1924

le of this patent: 10 377,845 Italy Jan. 10, 1940 

